Anchor escapement for timepieces



g- 1967 JEAN-CLAUDE SCHNEIDER 3,335,562

ANCHOR ESCAPEMENT FOR TIMEPIECES Filed March 3, 1965 2 Sheets-Sheet 1INVEN TOR 1 TEAN-CLnuJc SJINHJEIZ @zgmzimwmw Wis {M g 1957 JEAN-CLAUDESCHNEIDER 3,335,552

ANCHOR ESCAPEMENT FOR TIMEPIECES Filed March 5, 1965 2 Sheets-Sheet 3 &

M 7/ m V5 III: w m /m 1 2 n 0/ n) w y N n y) f m Z INVENTOR IEAN-CLHLIJE Schweidan 22.2mm Mum His United States Patent 3,335,562 ANCHORESCAPEMENT FOR TIMEPIECES Jean-Claude Schneider, La-Chaux-de-FondsNeuenburg,

Switzerland, assignor to Fabrique dHorlogerie Chs.

Tissot et Fils S.A., Le Locle, Neuenburg, Switzerland,

a corporation of Switzerland Filed Mar. 3, 1965, Ser. No. 436,777Claims. (Cl. 58122) The present invention has reference to an improvedanchor or lever escapement for timepieces, specially clockworks, whereinthe anchor body is equipped with shoulder means and limit stops, thelimit stops cooperating with an escape wheel in order to limit theamplitude of vibration or oscillation of the aforesaid anchor body.

Escapements of this type have been developed with the intention ofsimplifying assembly of the escapement in that there was avoided the useof reversing or turning pegs which generally are arranged to both sidesof the anchor staff and are embedded in a plate. The known anchors whichare equipped with limit stops cooperable with the escapement wheelpossess adjustable shoulders, this being the case with most conventionalanchors. These shoulders are secured by means of suitable adhesivematerial in recesses inset in the anchor body. Since the limit stopsfunction to act upon the drive surface of one of the teeth of theescapement wheel at the moment that the appropriate shoulder interruptsrotational movement of the escapement wheel at the desired position, itis necessary that the limit stops are adjusted in accordance with themomentary position of the corresponding shoulder.

In some cases the function of the limit stop is taken up itself by theshoulder. This shoulder then abuts against the base of the tooth, beforethe surface or plane of rest of the tooth impacts against the plane ofrest of the shoulder. This means that in this case the base portion ofthe tooth must be differently constructed than is otherwise usual.However, if the limit stops differ from the shoulder elements then theycannot be formed by appropriate portions of the anchor body. This is sobecause the adjustment of the impact position in correlation with thetemporary position of the shoulder would then no longer be possible. Inorder to circumvent this difliculty it has been attempted to equip theanchor with two adjustable elements. Each of both of the anchor clawstherefore possesses two recesses which are arranged in the directneighborhood of one another and in which always one element engages,such element generally being formed of ruby stone or glass. In so doing,one of both of these elements partakes the function of a shoulder, theother the function of the limit stop. Each limit stop is disposed in theregion of the corresponding shoulder at the side opposite the directionof rotation of the escapement wheel. Due to such arrangement theconstruction of the anchor is more difiicult and complicated.Consequently, the discussed physical construction can hardly be embodiedin smaller timepieces, such as for instance used in wrist watches.

Accordingly, it is a primary object of the present invention to providean improved construction of anchor escapement of the previouslymentioned type, the technical construction and assembly of which aresimpler than with conventional constructions, however without impairingthe precision of the entire assembly with regard to faultless operation.

Another important object of the present invention is concerned with animproved construction of anchor escapement for timepieces which ishighly reliable in operation, easy to assemble, economical tomanufacture as well as quite robust.

' Still a further extremely important object of this in- 3,335,562Patented Aug. 15, 1967 vention has reference to an improved anchorescapement of the type described wherein the anchor member incorporatesdrive shoulder means and limit stops, wherein the anchor member, theshoulder means and limit stops are integral with one another, therebyconsiderably simplifying manufacture and assembly of the escapement.

In order to implement these and still further objects of the invention,the anchor escapement designed according to the teachings of the presentinvention is generally characterized by the features that the shouldersand limit stops are formed from one piece together with the anchor body,and further, that the momentary contact or working surfaces of theanchor body are defined by peripheral surface elements of theaforementioned piece which are substantially axially parallely disposedto the axis of rotation of the anchor body.

Other features, objects and advantages of the present invention willbecome apparent by reference to the following detailed description anddrawings in which:

FIGURE 1 is an elevational view of a preferred embodiment of inventiveanchor escapement; and

FIGURE 2 is a cross-sectional view of the device of FIGURE 1substantially taken along the line IIII thereof, and wherein certainelements are particularly illustrated in detail.

Describing now the drawings and, in particular, directing attention toFIGURE 1 there is shown therein an anchor member or body 1 which is asingle piece worked by a punching and planing operation from a metalplate. This anchor body 1 cooperates with an escape or escapement wheel2 of conventional construction. This escape ment wheel 2 is providedwith a plurality of spaced teeth 3, each tooth possessing a drivesurface 4. Moreover, this anchor body 1 possesses two claws or pallets5. In the neighborhood of the free end portions 5a of each of theseclaws 5 there is located a respective shoulder 6 bounded by a linearface or edge 7. Each shoulder 6 is directed such that the face or edge 7providing a working surface abuts against the drive surface 4 of a tooth3 of the escapement wheel 2 at the moment when the anchor body 1 is justlocated in one of its outermost or terminal oscillating positions. Itwill be appreciated that each shoulder 6 provides limit stop means forthe anchor body 1. Apart from the physical structure just described,each claw 5 possesses a further shoulder 8 having the function of adrive shoulder and which according to the illustration of FIGURE 1 forthe claw 5 at the right side is pressed upwardly to the right. Eachshoulder 8 is disposed at the right of its associated shoulder 6,however at the same claw 5. Furthermore, each of the shoulders 8possesses a flat planed or trued drive or rear working surface 9possessing the function of a drive surface for the drive shoulder 8.Additionally, each such shoulder 8 has a lateral surface 10 which, withrespect to the rear. drive surface 9, forms an exactly defined angle.This lateral or side surface 10 provides a rest or stop surface for itsassociated drive shoulder 8.

The anchor body 1 has an elongated portion which is designated as theanchor rod or staff 11. At the outermost end of the anchor rod 11 thereis located a widened terminal piece 12 possessing an opening 13. Thisopening 13 forms an inlet for the entrainment means 24 of the spring pinor lug and which is advantageously manufactured in the same punching andtruing operation where also the shoulders 8 and 6 are produced. Thewidened end or terminal piece 12 of the anchor rod 11 is furthermoreworked into such a configuration that its forward face or edge 14 at thehighest location possesses a projection 15 constructed in the form of anose member. Due to milling out a circular-shaped edge 16 there remainsonly a thin wall 17 at the widened terminal piece 12 in front of theopening 13. The nose member 15 is located substantially centrally of theforward face 14 of this thin wall 17. Moreover, the lower face or wall17a of the thin wall 17 aligns with the lower boundary surface 1a of theanchor body 1.

By further referring to FIGURE 1 it will be apparent that twosymmetrically arranged elements forming horns 18 are bounded by thecircular-shaped edges 16 between the opening 13 and the forward face 14of the widened terminal piece 12. The described escapement has thefunction of controlling the vibrations or oscillations of a balancewheel 19, partially visible in FIGURE 2. This figure shows that a shaft20 of the balance wheel 19 supports a ring element 21 incorporating twocollars 21a and 21b providing a large cam disk 22 and smaller cam disk23 respectively. The upper circular-shaped cam disk 22, constructed asthe large cam disk, possesses a laterally protruding entrainment member24 engageable with the opening 13 of the terminalpiece 12. Thisentrainment member 24 can be obtained by punching and planing or truingoperations. A recess 25 formed at the marginal zone of the small camdisk 23 enables entry of the nose member 15.

The oscillatory or rocking movement of the anchor body 1 is ensured by asupport member 26 produced at an automatic lathe for instance. Thissupport member 26 incorporates two support arms 39, and a pin or pegstub 27, preferably integral therewith, which is arranged at the centralregion thereof and which engages in a bore 28 of the anchor body 1.Support member 26 is connected to a plate 29 of the timepiece by meansof screws 30 or equivalent fastening expedients. By means of thesescrews 30 a small plate 31 extending above the anchor body 1 isconnected to the support member 26. Furthermore, the support member 26is provided at its upper surface with an annular or ring rib 32 whichextends substan-' tially concentric to the pin stub or shaft 27 aboutwhich the anchor body 1 oscillates. Anchor body 1 bears by means of itsanchor staff or rod 11 upon this annular rib 32. As should be apparentby inspecting FIGURE 2, the clearance or play of the anchor body 1towards the top is formed by the spacing between the upper plane surface33 of the annular or ring rib 32 and the likewise fiat constructedsurface 34 of the small plate 31. Additionally, the support member 26has a preferably integral cylindrical-shaped pin or peg stub 35, thefunction of which will be considered shortly.

Both the arrangement as well as also the alignment of the support member26 upon or with respect to the plate 29 is eifected by thecylindrical-shaped pin 35 extending out of the support member 26 and bya cylindrical head bolt 36. The plate 29 is provided with two bores 37and 38, bore 37 receiving the pin 35 and the other bore 38 the bolt 36.The first bore 37 of both bores 37 and 38 is accommodated without playto the diameter of the pin 35, whereas the second bore 38 isaccommodated by frictional contact to the diameter of the pin 36. Thebolt 36 is pressed into the bore 38, whereas the widened cylinder head43 of bolt 36 engaging between the support arms 39 ensures for an exactorientation or alignment of the support member 26.

As will be recalled the described anchor body 1 is advantageouslymanufactured from a single piece. The operative steps necessary for themanufacture of this member can be reduced to a minimum. This anchor bodyor member 1 can be completely manufactured within the framework of apunching and milling operation. All of the working portions of theanchor 1, the nose member 15, the entrainment opening 13, the shoulders8, the limit,

stops 6 and the pivot recess are thereupon simultaneously trued(subsequently punched). As a result, the anchor body or member 1 forexample can be formed from a light metal or alloy plate, such asanticordal. In order to impart to the working surfaces of the anchorbody 1 a hardness and durability which is substantially wear resistantit is possible to expose the anchor to an appropriate treatment. To thisend, in the, first instance reference is made to an anodic oxidationprocess (eloxation process) which does not in any way change thedimensions of the parts of the anchor.

Due to the fact that all of the working surfaces of the anchor and aboveall the working surfaces of the limit stops as well as the shoulders andthe inner surface of the central bore of the anchor provide peripheralor marginal surface portions of the same piece which are disposedsubstantially axially parallel to the axis of to tation of the anchor,such can also be conjointly planed in the same working operation. Thistakes place with the aid of a punch press and a single tool by means ofwhich the necessary precision can be achieved, so that no additionaladjustment is necessary.

The herein described anchor can also be manufactured by means of aninjection molding process from plastic material. The same holds true formanufacturing by sintering with self-lubricating materials. Finally, thenose member at the forward face of the thin wall, depending upon theconditions of installation of the balance wheel, can also extend up tothe height of the upper surface of the anchor body, whereby the horns 19must extend lower than the nose member 15.

While there is shown and described present preferred embodiment of theinvention it is to be distinctly understood that the invention is notlimited thereto but may be otherwise variously embodied and practisedwithin the scope of the following claims.

What is claimed is:

1. Anchor escapement for timepieces comprising an anchor body mountedfor oscillatory movement about an axis of rotation, an escape wheelpositioned to cooperate with said anchor body, said anchor bodyincluding drive shoulder means and limit stop means, said limit stopmeans cooperating with said escape wheel to limit the amplitude ofoscillation of said anchor body, said drive shoulder means and saidlimit stop means being integral with said anchor body, both said driveshoulder means and said limit stop means possessing working surfacesdefined by peripheral surface elements which are arranged substantiallyaxially parallel to said axis of rotation of said anchor body, saidescape wheel including a plurality of spaced teeth, each of said teethhaving a drive surface, said anchor body incorporating a pair of clawmembers, each of said claw members including a shoulder bounded by alinear edge portion and defining said limit stop means, said shoulderforming a flat surface portion bearing against a drive surface of agiven one of said teeth of said escape wheel at the moment said anchorbody is located in one of its terminal oscillatory positions, each clawmember further incorporating a shoulder defining said drive shouldermeans, said drive shoulder means cooperating with said respective drivesurfaces of said teeth of said escape wheel in order to impart oscil-.latory motion to said anchor body, said drive shoulder .means of eachclaw member possessing a flat surface portion providing a drive surfacefor said associated drive shoulder means, a lateral surface portionlocated at said driveshoulder means at a predetermined angle withrespect to its associated flat surface portion, said lateral surfaceportion providing a rest surface for the correspending drive shouldermeans, with a tooth of said escape wheel contacting said lateral surfaceportion of one of said claw members in each one of said terminaloscillatory positions.

2. Anchor escapement for timepieces comprising an anchor body mountedfor oscillatory movement about an axis of rotation, an escape wheelpositioned to cooperate with said anchor body, said anchor bodyincluding drive shoulder means and limit stop means, said limit stopmeans cooperating with said escape Wheel to limit the amplitude ofoscillation of said anchor body, said dri Shou der means and said limitstop m ns ing integral with said anchor body, both said drive shouldermeans and said limit stop means possessing working surfaces defined byperipheral surface elements which are arranged substantially axiallyparallel to said axis of rotation of said anchor body, a support memberserving as guide means for the oscillatory movement of said anchor body,said support member having a pair of spaced, symmetrically disposedsupport arms between which there is provided a recess, a pin stubcarried by said support member and projecting out of the latter to oneside, said anchor body being provided with a bore, said pin stubengaging with said bore.

3. Anchor escapement for timepieces as defined in claim 1 including asupport member serving as guide means for the oscillatory movement ofsaid anchor body, said support member having a pair of spaced,symmetrically disposed support arms between which there is provided arecess, a pin stub carried by said support member and projecting out ofthe latter to one side, said anchor body being provided with a bore,said pin stub engaging with said bore.

4. Anchor escapement for timepieces as defined in claim 3 furtherincluding a plate, fastening means for connecting said support memberwith said plate.

5. Anchor escapement for timepieces as defined in claim 4 wherein afurther plate is connected to one side of said anchor body by saidfastening means.

6. Anchor escapement for timepieces as defined in claim 5 wherein saidsupport member is provided with a substantially ring-shaped ribconcentrically arranged with respect to said pin stub, said anchor bodybearing via its anchor rod against said ring-shaped rib, said anchorbody being located with a certain play between said ring-shaped rib andsaid further plate.

7. Anchor escapement for timepieces as defined in claim 6, furtherincluding bolt means carried by said plate, said pin stub and said boltmeans being positioned so as to insure for the arrangement andorientation of said support member with resnect to said plate.

8. Anchor escapement for timepieces comprising an anchor body mountedfor oscillatory movement about an axis of rotation, an escape wheelpositioned to cooperate with said anchor body, said anchor bodyincluding drive shoulder means and limit stop means, said limit stopmeans cooperating with said escape wheel to limit the amplitude ofoscillation of said anchor body, said drive shoulder means and saidlimit stop means being integral with said anchor body, both said driveshoulder means and said limit stop means possessing working surfacesdefined by peripheral surface elements which are arranged substantiallyaxially parallel to said axis of rotation of said anchor body, saidanchor body further including a relatively thin wall, a nose memberprovided at said relatively thin wall, said relatively thin wall beingaligned with a surface of said anchor body, said anchor bodyadditionally including a pair of horn members between which saidrelatively thin wall extends, each side of said thin wall beingintegrally connected with the associated horn member, said anchor bodyhaving an anchor rod provided with a widened terminal piece at the endthereof remote from said drive shoulder means and limit stop means, saidwidened terminal piece having an opening, an entrainment member enteringsaid opening, said widened terminal piece including a face portion, aprojection constructed to define said nose member located atthe highestpoint of said face portion, said widened terminal piece being providedat its upper end with a circular-shaped edge formed such that saidrelatively thin wall only remains above said opening which merges with asurface of said anchor body, said pair of spaced horn members beingarranged substantially symmetrical to the lengthwise aXis of said anchorrod, said pair of horn members being disposed between said opening andsaid face portion of said widened terminal piece.

9. Anchor escapement for timepieces, comprising an anchor body mountedfor oscillatory movement about an axis of rotation, an escape wheelpositioned to cooperate with said anchor body, said escape wheelcomprising a plurality of teeth each having a flat drive surface and alinear edge portion extending at the forward end of said drive surfacesubstantially parallel to the axis of the escape wheel, said anchor bodycomprising a pair of drive shoulder means and limit stop means, saiddrive shoulder means each comprising a flat drive surface and a stopsurface, said teeth and drive shoulder means being arranged in such amanner that each tilting movement imparted to the anchor body isprovided by the flat drive surface of one of said teeth and one of saiddrive shoulder means acting successively, said limit stop means eachcomprising a plane surface portion arranged to abut when the anchor bodyis in a given one of its terminal positions, the flat drive surface ofthat tooth wherein the linear edge thereof engages with thecorresponding stop surface of the anchor body thus limiting theamplitude of oscillation of said anchor body, said limit stop means anddrive shoulder means being integral With said anchor body.

10. Anchor escapement according to claim 9, wherein said anchor body isformed of a substantially plane plate member, said limit stop means eachextending on the same side of a corresponding one of said drive shouldermeans, said plate member being provided along its periphery with a pairof recesses, each of said recesses being located between one of saidlimit stop means and the corresponding one of said drive shoulder means.

References Cited UNITED STATES PATENTS 256,708 4/1882 Lane 58-421348,980 9/1886 Lane 58-121 RICHARD B. WILKINSON, Primary Examiner.

GERALD F. BAKER, Examiner. MICHAEL L. LORCH, Assistant Examiner,

1. ANCHOR ESCAPEMENT FOR TIMEPIECES COMPRISING AN ANCHOR BODY MOUNTEDFOR OSCILLATORY MOVEMENT ABOUT AN AXIS OF ROTATION, AN ESCAPE WHEELPOSITIONED TO COOPERATE WITH SAID ANCHOR BODY, SAID ANCHOR BODYINCLUDING DRIVE SHOULDER MEANS AND LIMIT STOP MEANS, SAID LIMIT STOPMEANS COOPERATING WITH SAID ESCAPE WHEEL TO LIMIT THE AMPLITUDE OFOSCILLATION OF SAID ANCHOR BODY, SAID DRIVE SHOULDER MEANS AND SAIDLIMIT STOP MEANS BEING INTEGRAL WITH SAID ANCHOR BODY, BOTH SAID DRIVESHOULDER MEANS AND SAID LIMIT STOP MEANS POSSESSING WORKING SURFACESDEFINED BY PERIPHERAL SURFACE ELEMENTS WHICH ARE ARRANGED SUBSTANTIALLYAXIALLY PARALLEL TO SAID AXIS OF ROTATION OF SAID ANCHOR BODY, SAIDESCAPE WHEEL INCLUDING A PLURALITY OF SPACED TEETH, EACH OF SAID TEETHHAVING A DRIVE SURFACE, SAID ANCHOR BODY INCORPORATING A PAIR OF CLAWMEMBERS, EACH OF SAID CLAW MEMBERS INCLUDING A SHOULDER BOUNDED BY ALINEAR EDGE PORTION AND DEFINING SAID LIMIT STOP MEANS, SAID SHOULDERFORMING A FLAT SURFACE PORTION BEARING AGAINST A DRIVE SURFACE OF AGIVEN ONE OF SAID